I'm using an Arduino with some load cells to collect weight data over long periods of time (days etc.) and I'm using a 12V lead-acid motorcycle battery to power the entire thing. My electronics only need 7V to operate, so I am essentially wasting 5/12 (~40%) of the power. The entire setup only draws about 20mA, so I cannot use a DC to DC converter because they have a no-load current of 10mA which is too much. Is there anything else I can do to save that power and extend battery life?